Virtual universes (VUs) or virtual worlds are computer-based simulated environments intended for its users or residents to inhabit and interact via avatars, which are personas or representations of the users of the virtual universes. These types of virtual universes are now most common in multiplayer online games, such as Second Life®, which is a trademark of Linden Research Inc. in the United States. Avatars in these types of virtual universes, which can number well over a million, have a wide range of business and social experiences.
It is possible for these VUs to be quite complex, with each VU or region within the VU having a large number of avatars, objects, texts and scripts for desired visual and functional effects. However, visually complex VUs can make it difficult for vision impaired users, as well as non-vision impaired users, to identify and distinguish objects in the virtual universe.